1668717511 has 2 divisors, whose sum is σ = 1668717512. Its totient is φ = 1668717510.

The previous prime is 1668717409. The next prime is 1668717517. The reversal of 1668717511 is 1157178661.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1668717511 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1668717517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 834358755 + 834358756.

It is an arithmetic number, because the mean of its divisors is an integer number (834358756).

Almost surely, 2^1668717511 is an apocalyptic number.

1668717511 is a deficient number, since it is larger than the sum of its proper divisors (1).

1668717511 is an equidigital number, since it uses as much as digits as its factorization.

1668717511 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 70560, while the sum is 43.

The square root of 1668717511 is about 40849.9389350829. The cubic root of 1668717511 is about 1186.1172111293.

The spelling of 1668717511 in words is "one billion, six hundred sixty-eight million, seven hundred seventeen thousand, five hundred eleven".